1. sealed关键字
当对一个类应用 sealed 修饰符时,此修饰符会阻止其他类从该类继承。类似于Java中final关键字。
在下面的示例中,类 B 从类 A 继承,但是任何类都不能从类 B 继承。
2. sealed 修饰方法或属性
能够允许类从基类继承,并防止它们重写特定的虚方法或虚属性。
1)sealed是对虚方法或虚属性,也就是同override一起使用,如果不是虚方法或虚属性会报出错误:cannot be sealed because it is not an override
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public class D { /* ConsoleApplication1.MSFun.Sealed.D.M()' * cannot be sealed because it is not an override */ public sealed void M() { Console.WriteLine("D.M()"); } }
2)防止子类重写特定的方法或属性
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
public class A { protected virtual void M() { Console.WriteLine("A.M()"); } protected virtual void M1() { Console.WriteLine("A.M1()"); } } public class B : A { protected sealed override void M() { Console.WriteLine("B.M()"); } protected override void M1() { Console.WriteLine("B.M1()"); } } public sealed class C : B { /* ConsoleApplication1.MSFun.Sealed.C.M()': * cannot override inherited member 'ConsoleApplication1.MSFun.Sealed.B.M()' * because it is sealed */ //protected override void M() { Console.WriteLine("C.M()"); } protected override void M1() { Console.WriteLine("C.M1()"); } }